tetragon

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// SPDX-License-Identifier: Apache-2.0
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// Copyright Authors of Tetragon
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package mountinfo
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import (
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	"fmt"
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	"os"
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	"syscall"
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	"testing"
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)
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func TestIsMountFS(t *testing.T) {
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	type args struct {
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		infos     []*MountInfo
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		typ, root string
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	}
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	type want struct {
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		mounted, instance bool
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	}
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	tests := []struct {
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		name            string
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		args            args
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		want            want
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		preRun, postRun func()
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	}{
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		{
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			name: "/sys/fs/bpf empty directory",
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			args: args{
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				infos: []*MountInfo{
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					{
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						Root:           "/",
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						MountPoint:     "/tmp/sys/fs/bpf",
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						FilesystemType: FilesystemTypeBPFFS,
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					},
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				},
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				typ:  FilesystemTypeBPFFS,
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				root: "/tmp/sys/fs/bpf",
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			},
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			want: want{
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				mounted:  true,
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				instance: true,
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			},
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			preRun: func() {
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				mountFS("/tmp/sys/fs/bpf", FilesystemTypeBPFFS)
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			},
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			postRun: func() {
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				syscall.Unmount("/tmp/sys/fs/bpf", 0)
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				syscall.Rmdir("/tmp/sys/fs/bpf")
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				syscall.Rmdir("/tmp/sys/fs")
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				syscall.Rmdir("/tmp/sys")
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			},
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		},
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		{
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			name: "/sys/fs/bpf not mounted",
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			args: args{
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				infos: []*MountInfo{
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					{},
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				},
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				typ:  FilesystemTypeBPFFS,
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				root: "/sys/fs/bpf",
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			},
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			want: want{
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				mounted:  false,
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				instance: false,
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			},
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			preRun:  func() {},
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			postRun: func() {},
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		},
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	}
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	for _, tt := range tests {
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		t.Run(tt.name, func(t *testing.T) {
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			tt.preRun()
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			defer tt.postRun()
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			m, i := IsMountFS(tt.args.infos, tt.args.typ, tt.args.root)
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			infos, _ := GetMountInfo()
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			for _, v := range infos {
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				fmt.Printf("%+v\n", *v)
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			}
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			switch {
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			case m != tt.want.mounted, m != tt.want.instance:
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				t.Errorf("IsMountFS() = got (%v,%v), want (%v,%v)",
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					m, i, tt.want.mounted, tt.want.instance)
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			}
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		})
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	}
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}
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// Copied from pkg/bpf/bpffs_linux.go. The reason it was not exported inside
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// and used here is because importing that package would introduce an import
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// cycle.
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func mountFS(root, kind string) error {
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	mapRootStat, err := os.Stat(root)
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	if err != nil {
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		if os.IsNotExist(err) {
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			if err := os.MkdirAll(root, 0755); err != nil {
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				return fmt.Errorf("unable to create %s mount directory: %s", kind, err)
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			}
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		} else {
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			return fmt.Errorf("failed to stat the mount path %s: %s", root, err)
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		}
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	} else if !mapRootStat.IsDir() {
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		return fmt.Errorf("%s is a file which is not a directory", root)
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	}
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	if err := syscall.Mount(root, root, kind, 0, ""); err != nil {
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		return fmt.Errorf("failed to mount %s %s: %s", root, kind, err)
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	}
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	return nil
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}
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